Advisory Council on the Environment

At its meeting of 3 May 1999, the Environmental Impact Assessment (EIA) Subcommittee considered and endorsed the Supplementary EIA Report for Clinical Waste Disposal at Chemical Waste Treatment Centre. The Subcommittee also endorsed by circulation before the meeting the Environmental Study Report of the Dualling of Hiram's Highway between Clear Water Bay Road and Marina Cove and Improvement to the Local Access to Ho Chung.

ADVICE SOUGHT

2.Members are requested to advise whether the two reports mentioned above should be endorsed.

3.The Chemical Waste Treatment Centre (CWTC) is a Designated Project exempted under S.9(2)g of the EIA Ordinance, as it was commissioned in April 1993 before the enactment of the Ordinance. An EIA Study on the CWTC was conducted in 1991 and endorsed by the then Environmental Pollution Advisory Committee. The project will involve physical modifications to the existing CWTC for accepting and treating clinical waste.

4.The major issues identified include operational air emission, water quality and waste disposal, other construction impacts and hazards. On air quality, the assessment concluded that adverse impacts are not expected, even if no additional mitigation measures are provided during the incineration of clinical waste. Meanwhile, the project will not affect the effluent discharge from the facility and there will be no additional water quality impacts. The existing standards will continue to be applied and no further mitigation measures are required.

5.All solid residues arising from the incineration of clinical waste will be chemically stabilized and tested prior to disposal to landfill. The potential environmental impacts associated with solid waste disposal meet the existing guidelines and no additional mitigation measures are required. On the other hand, construction noise and dust impacts from on-site construction activities will be within the existing standards. The nearest residential uses are about 1500 meters away.

6.In terms of the potential hazards, the assessment shows that the combined handling, storage, treatment and disposal of chemical and clinical waste at the CWTC is feasible and acceptable from a risk perspective, subject to implementation of the recommendations which have been made. The proposed Clinical Waste Control Scheme, which includes the implementation of the Draft Code of Practice and incineration of waste at the CWTC will be an improvement on existing practice from a risk perspective. No additional mitigation measures are required.

Views and Recommendations of EIA Subcommittee's Members

7.Members discussed the report at the meeting. Queries mainly focussed on the exceedance of mercury level against the required emission standards in the trial burn of clinical waste at the CWTC.

8.The project proponent clarified that they were confident about meeting the emission standard of mercury should the existing carbon injection system at the CWTC, which was not activated during the trial burn, be used in the operation. Meanwhile, good management practice and monitoring systems would be adopted to further safeguard the process. The former would include the development and implementation of the Code of Practice which required hospitals and clinics to segregate mercury, a kind of chemical waste, from clinical waste for disposal purpose. The latter would involve constant monitoring of the concentration level of mercury to ensure the required degree of mercury removal was attained at all time.

9.The project proponent also confirmed that a performance test would be conducted before the operation of the clinical waste handling facilities. The operator had a contractual obligation to demonstrate compliance with all stipulated technical standards to the satisfaction of EPD. Also, more stringent requirements in the EM&A programme would be adopted for continuous monitoring of mercury.

10.The Subcommittee agreed to recommend to the main Council to endorse the report with the following conditions:

Stringent requirements on mercury monitoring are incorporated into the EM&A programme of the CWTC;

Performance test is undertaken by the project proponent before the full operation of the clinical waste handling facilities in the CWTC; and

The ACE will be informed of any serious problem arising from the performance test or the operation.

Environmental Study Report of the Dualling of Hiram's Highway between Clear Water Bay Road and Marina Cove and Improvement to Local Access to Ho Chung
(ACE EIA Paper 10/99)

11.The project was proposed by Highways Department for relieving the overloaded and congested road conditions, as well as to eliminate the accident black spot at the junction of Hiram's Highway and Ho Chung Road. Since the future improved Hiram's Highway is classified as Rural Road (A) by Transport Department, the project is not a Designated Project under the EIA Ordinance. It consists of the improvement of the section of Hiram's Highway between Clear Water bay Road and Marina Cove from its existing 2-lane carriageway to a dual 2-lane standard carriageway, and provision of an access road from the improved Hiram's Highway to the Ho Chung area. The improvement works include cuttings of slope, construction of carriageways, a vehicular bridge, two pedestrian subways, the installation of noise barriers and compensatory planting schemes.

12.Traffic noise was identified as the major concern of the project. With direct mitigation measures including plain noise barriers and inclined cantilever inverted-L noise barriers in place, all the affected dwellings except 2 existing schools and 1 planned Comprehensive Development Area (CDA) will comply with the established noise standards. To mitigate the residual noise impact, the 2 schools will be provided with window insulation and air conditioning while the planned CDA will adopt site-specific building design. The future developer will need to take the noise constraints into account in preparing the Master Layout Plan of the CDA for approval under the Town Planning Ordinance.

Views and Recommendations of EIA Subcommittee's Members

13.Members expressed concerns on the loss of 1 hectare's wetland, in the form of abandoned agricultural land, in the project. The project proponent confirmed that field surveys had been conducted for the concerned area and no habitats or species of conservation interest were recorded. Compensatory planting would also be provided.

14.The Subcommittee agreed to recommend to the main Council to endorse the report without condition.